Picker stop mechanism



0a. I0 1937 D. M. PITTMAN 3,345,694

PI CKER STOP MECHANI SM Filed May 10, 1965 I?) i INVENTOR bAvxb M. PITTMAN ATTORNEY$ United States Patent Ofifice dfi iififi i Patented Oct. 10, 1967 3,345,694 PICKER STOP MECHANISM David M. Pittman, Fayetteville, N.C., assignor to Ideal Industries, Inc., Bessemer City, N.C., a corporation of North Carolina Filed May 10, 1965, Ser. No. 454,350 Claims. (Cl. 19.2)

ABSTRACT OF THE DISCLGSURE An electrical stop motion for a textile picker for stopping the picker upon detection of a foreign electrically conductive body in the textile lap being fed between a pair of calender rolls, and wherein one of the calender rolls has an electrically conductive roll surface electrically insulated from the frame of the picker with the other calender roll being grounded to the frame of the picker and normally out of contact with the other roll due to the presence of the lap of textile material therebetween. For avoidance of damage by electrical sparking setting fire to the textile material, a high input impedance electrical circuit is used for maintaining the roll surface of the first mentioned calender roll at a low electrical potential relative to the frame of the picker and to limit the current flowing upon completion of the circuit by a foreign conductive body bridging the gap between the calcuder rolls.

This invention pertains to a picker stop mechanism and, more particularly, to such a stop mechanism responsive to the passage of an undesirable foreign electrically conductive body such as a nut or bolt, to permit an operator to remove the foreign body and avoid subsequent damage to equipment processing the lap delivered from the picker.

In the manufacture of textile goods, such as cotton goods, the raw textile material enters the manufacturing process both dirty and compressed very tightly together with a random fiber orientation. Before a yarn may be produced from the raw textile material, the material must be opened from the compressed state, cleaned to remove the dirt and the process of fiber orientation begun by passing the material through a card. As generally known and used, a card or card machine begins the process of fiber orientation by passing the raw textile material between relatively moving toothed surfaces, known as a card cylinder and flats. The toothed surfaces of the card are formed by card clothing, and operate with a small clearance between the relatively moving surfaces. Entrance of foreign bodies into the card with the textile material being processed, such as apron spikes, spinning travelers, segments of bale strap, nuts, bolts and washers or other pieces of mill scrap will so damage the card clothing as to substantially impair the production of the card and require replacement of the card clothing, which is expensive both in terms of actual cost and downtime for the machine. Further, entrance of such foreign bodies of metal raises substantial danger of fire set in the textile material by sparks struck between the foreign body and the clothing.

Faced with these problems, textile engineers first proposed the use of magnets adjacent the lap of material entering the card, to attract any ferrous foreign body and remove it before it could enter and damage the card or cause fire. More recently, it has been proposed to provide a card with a stop motion operated in response to the passage of a foreign electrically conductive body past the card feed roll, intended to stop the card motion before the foreign body could come into contact with the card clothing. This stop mechanism is deficient in operation for a variety of reasons, including the nearness of the sensing position to the card clothing surface which requires rapid positive action in order to prevent damage to the clothing, the necessity of stopping production of a machine which produces higher quality products if allowed to operate continuously, and the cost of equipping all cards in a plant with such a stop mechanism. Further, the foreign bodies may still strike sparks from the card and cause fire in the card room with attendant danger to the mill building in which that room is located.

conventionally, cards are fed with a lap of textile material formed as a product by the picker or picker machine which performs steps of the opening and cleaning process. Due to the relative rates of production, one picker supplies a number of cards. Additionally, while card rooms are located in buildings with other machinery, picker rooms are usually separate from the main mill building as a precaution against any spread of fire. This invention proposes a stop mechanism to be applied to a picker to detect foreign electrically conductive bodies and permit their removal before the lap of material is introduced into the card. The deficiencies of prior art arrangements are thus avoided by separating the point of detection of the foreign body from the point where such a body might cause damage, permitting the cards to operate more effectively by running continuously, reducing the overall cost of a protective installation by substantially reducing the number of mechanisms required; and markedly reducing the danger of fire in the mill building including the card room by removing any possible danger to the picker room.

Accordingly, it is an object of this invention to provide a stop mechanism for a picker responsive to the detection of a foreign conductive body in the textile material passing through the picker for reducing the danger of damage to machinery or fire caused by the body.

A further object of this invention is to provide an improved picker in which a stop mechanism responsive to detection of a foreign conductive body in the lap delivered by the picker stops the picker to permit removal of the foreign body in order to avoid possible subsequent fire or damage to a card to which the lap is delivered for further operations.

Some of the objects of the invention having been stated, other objects will appear as the description proceeds, when taken in connection with the accompanying drawings, in which:

FIGURE 1 is a left hand side View of the delivery end of a picker embodying this invention;

FIGURE 2 is a delivery end view of the picker of FIGURE 1;

FIGURE 3 is a part sectional view of the calender and lap rolls of the picker of FIGURE 1,. with a schematic showing of the elements of the stop mechanism; and

FIGURE 4 is a part sectional view of the calender rolls of FIGURE 3.

Briefly, the improved picker of this invention has a stop mechanism responsive to a foreign electrically conductive body in the textile material lap electrically connecting two rolls maintained at different electrical potentials. An electrical relay means including a high input impedance electronic current amplifier and a relay responsive to the output of the amplifier operates in response to the foreign conductive body to control a mechanical means disengaging the drive of the picker.

The picker shown generally in FIGURES 1 and 2 is a well known conventional picker in which the drive for the rotating elements of the picker may be interrupted to stop the picker in response to certain occurrences during operation of the picker, such as the accumulation of a desired length of lap. In the conventional embodiment shown, the picker drive is disengaged by movement of a drop lever 11 With the drop lever 11]? in a raised position, as shown, the driving calender flange gear 11 engages the driven calender gear 12 to cause the picker to deliver a lap 13 of textile material. The drop lever is held in its raised position, with the drive engaged, by a knock off lever 14, which is moved in response to various machine conditions to release the drop lever 16 for movement to a position in which the driving engagement of the calender gears 11 and 12 is disengaged and delivery of a lap 13 is stopped. In applying this invention to such a conventional picker, a pressure fluid cylinder 15, such as a pneumatic or hydraulic cylinder, is mounted on the frame of the picker to engage the knock off lever 14. On actuation of the cylinder by application of pressure fluid, the knock off lever 14 is moved to release the drop lever 10 and disengage the picker drive, stopping delivery of a lap 13. The cylinder 15 has been shown as applied to a conventional and well known picker in which drive engagement is controlled by the operation of a drop lever 10. Where a picker has been modernized by replacing the drop lever control over drive engagement by some other control such as a pressure fluid or electrical clutch, the stop mechanism of this invention may be applied to control clutch engagement, instead of governing the position of a drop lever.

An electrical means for controlling the mechanical means which disengages the picker drive is shown in FIG- URE 3 where a conventional picker machine has a number of calender rolls supported for rotation about horizontal anes by the picker frame, through and around which the lap 13 passes before being delivered to the lap rolls 16, 17 to be wound into a lap 13 for subsequent handling. In accordance with this invention, one calender roll is formed with a roll surface 20 which is electrically insulated from the roll shaft 21 by a sleeve 22 of an insulating material such as nylon positioned between the shaft 21 and surface 20. The other calender rolls 23, 24, 25 may be of the conventional all metal construction, and are in electrically conductive relation, or in circuit, with the picker frame. As indicated schematically, these other calender rolls 23, 24, 25 may be considered as at ground potential. The roll surface 20 of the insulated calender roll is engaged by a brush 26, made of carbon or any other suitable material, and supported by a bracket 27 and spring 30 from the frame of the picker. The brush 26 is insulated from the frame of the picker and is at an electrical potential applied from an electrical relay circuit which will be described in detail. Normally, the insulation of the brush 26 and roll surface 20 from the picker frame permits those elements to be held at an electrical potential relative to the remainder of the picker. However, when the lap 13 does contain an objectionable foreign electrically conductive body picked up during some prior stage of the manufacturing process which would be dangerous in the next subsequent manufacturing process, such as a nut or bolt, the passage of such a body 31 through the nip formed between the insulated calender roll and the next adjacent calender roll 23 electrically connects the insulated roll surface 20 and the next adjacent calender roll 23 to complete an electrical circuit. In this circumstance, due to the difference in electrical potential of the rolls, a current flows in this circuit and the stop mechanism responds to the foreign electrically conductive body by disengaging the machine drive.

In order to respond to the foreign electrically conductive body, an electrical relay circuit is provided which governs the operation of the mechanical means disengaging the picker drive. The electrical relay circuit includes an electronic current amplifier and a relay responsive to the output current of the amplifier to control the mechanical disengaging means. The current responsive relay may control the operation of an electrical solenoid valve, which in turn controls the admission of a pressure fluid to a pressure fluid cylinder 15 mounted on the frame of the picker to operate the knock off lever 14 and release the drop lever 10 to disengage the picker drive and to permit an operator to remove the foreign body 31 from the lap.

In order to provide for the safety of operators of the picker, the electrical potential applied by the relay circuit to the brush 2s and roll surface 20 is a relatively low potential. While that term, relatively low potential, may have various meanings depending upon the particular application being discussed, as here used it is intended to define an electrical potential sufficiently low to avoid injury to any person accidentally contacting the roll surface 20 while adequate to indicate the connection of the rolls by a foreign body. The particular potential applied is determined by certain circuit characteristics not yet discussed, but made clear below.

Further, in order to avoid sparking at the calender roll surfaces on connection of the rolls by a foreign electrically conductive body, entering the nip, with the attendant dangers of setting fire to the textile fibers forming the lap, this invention uses a high input impedance circuit which serves, in conjunction with the relatively low potential, to limit the current flowing on connection by a foreign conductive body, and thus markedly reduce the possibility of sparking. The high input impedance circuit is shown in FIGURE 3, and uses an electronic current amplifier 32 to amplify the relatively small current flowing at the circuit input on connection of the rolls. The output of the electronic current amplifier provides a current adequate to operate a relay which governs the operation of the mechanical means for disengaging the picker drive. As illustrated, the electronic current amplifier 32 employs a triode vacuum tube 313, with the power required for operation of the triode supplied from a power transformer 34. One winding of the transformer supplies a relatively low voltage to operate the vacuum tube heater 35, and to bias the grid 36 of the triode. The grid bias voltage is applied through a diode D1 and a bias resistor Rl, selected to apply an approximately DC voltage of the required bias potential to the grid 36 to prevent current flow between the plate 37 and cathode 40 of the triode. The relatively low potential applied to the insulated roll surface 20 by the brush 26 is obtained from the grid bias voltage, through a current limiting resistor R2. Thus, the amplifier input connections are to the grid 36 to which the brush 26 is connected and the grounded cathode 40.

Another winding of the transformer 34 applies a higher voltage to the plate 37 of the triode 33, through a circuit including a capacitor C-1 with amplifier output connections at the terminals of the capacitor and a current responsive relay RE-l connected across the output connections as an output load. The armature of the current responsive relay RE-l controls the operation of relay contacts which switch the application of current to a solenoid valve 41, which governs the application of pressure fluid from any suitable source to the fluid cylinder 15 and thus the disengagement of the drive.

In operation, so long as the insulated roll surface 20 is maintained at an electrical potential relative to the remainder of the picker machine, the grid 36 of the triode 33 is so biased as to prevent current flow through the plate circuit, including the current responsive relay IRE-1. On connection of the roll surface 20 and the next adjacent roll 23 by a foreign electrically conductive body 31,

a the bias potential of the grid 36 is so modified by the amplifier input current flow through the resistor R2 and the rolls as to permit the flow of current between the plate 37 and cathode 44) of the triode 33. The flow of current through the plate circuit at the amplifier output actuates the current responsive relay RE-l connected to the output, to switch the relay contacts controlling the operation of the solenoid valve 41.

While it is within the skill of persons familiar with the electronic arts to design high input impedance electronic current amplifiers using either vacuum tubes or other an electronic current amplifier having input connecavailable devices, the circuit shown in FIGURE 3 has tions, and

operated satisfactorily where the following components brush means operatively connected to one amplifier Were used. input connection for connecting the amplifier and 5 the roll surface of the first roll.

Trlode 33 6C4. 3. The combination claimed in claim 1, in which the Transformer 34 Merit P-3046. means associated with the circuit means and machine D-l 1N3254. drive comprises:

Resistor ohm /2 Watt. an electrical relay responsive to electrical connection Resistor R-2 lkilohm /2 watt. of the roll surface of the first roll and the second Capacitor C-l 8 microfarad. roll, and

Relay Potter Bfllmfield KAPUD mechanical means responsive to relay actuation for disengaging the machine drive. 4. In combination with a picker machine delivering a 5 lap of textile material and having a frame and a controllable drive, an apparatus for stopping the picker on detection of a foreign electrically conductive body in the lap, the apparatus comprising:

a first calender roll having an electrically conductive roll surface electrically insulated from the frame,

a second calender roll in electrically conductive relation to the frame and normally out of contact with the roll surface of the first roll, high input impedance electronic current amplifier 5 having input connections operatively associated with the roll surface of the first roll and maintaining the roll surface of the first roll at a low electrical potential relative to the frame and having output connections at which an electrical current flows in response to a foreign electrically conductive body connecting the roll surface of the first roll and the second roll to complete an input circuit, an electrical relay operatively associated with the amplifier output and responsive to output current flow, and

mechanical means operatively associated with the electrical relay and the machine drive and responsive to operation of the relay for disengaging the picker drive. 5. The combination claimed in claim 4, in which the mechanical means comprises:

a solenoid valve operatively associated with the relay and responsive to the relay to control a pressure As shown in FIGURE 3, the current responsive relay RE-l controls the application of current to a solenoid valve 41. The solenoid valve, in turn, controls the application of pressure fluid to the pressure fluid cylinder 15, which acts to disengage the picker drive. Where the picker under consideration has been modernized, by the addition of a clutch, the solenoid valve may be employed to control the operation of a pressure fluid clutch, or the relay RE-l may directly control an electrical clutch.

In operation, the actuation of the current responsive relay RE-l in response to the output of the current ama plifier actuates the solenoid valve 41 to cause the application of pressure fluid to the pressure fluid cylinder 15, moving the knock ofl? lever 14 and releasing the drop lever 10 to move to a downward position at which the picker drive is disengaged. With the drive disengaged, the picker operator may remove the electrically conductive 0 foreign body 31 from the lap 13, adjacent the nip at which the foreign body 31 was detected, and then re-engage the picker drive to again begin operation of the machine.

In the drawings and specification there has been set forth a preferred embodiment of the invention and, although specific terms are employed, they are used in a generic and descriptive sense only and not for purposes of limitation, the scope of the invention being defined in the claims.

I Claim:

1. In combination with a picker machine delivering a lap of textile material and having a frame and a controllable drive, an apparatus for stopping the picker on detection of a foreign electrically conductive body in the fl id and the apparatus comprising: 45 a fiuid cylinder operatively associated with the solenoid a first calender roll having an electrically conductive valve and responsive to the valve to disengage the roll surface electrically insulated from the frame, picker drive a second calender roll in electrically conductive rela- References Cited tion to the frame and normally out of contact with the roll surface of the first roll, UNITED STATES PATENTS high input impedance electrical circuit means electrical- 1,721,077 7/1929 Le Blan 19-.23 ly connected to the roll surface of the first roll for 2,102,906 12/1937 Merchant 19-.22 maintaining the roll surface of the first roll at a 2,748,381 5/ 1956 Baker 200-61.13 low electrical potential relative to the frame, and 3,092,875 6/1963 McLean 19-.23 means operatively associated with the circuit means 3, 04,054 8/1965 Oucllette 200-61.09

and machine drive for disengaging the machine drive FOREIGN PATENTS in response to a foreign electrically conductive body electrically connecting the roll surface of the first 7,350 11/1905 Great Bmam' roll and the second roll. l 2. The combination claimed in claim 1, in which the 0 MERVIN STEIN P r 1mm y Exammer' circuit means comprises: I. C. WADDEY, Assistant Examiner. 

1. IN COMBINATION WITH A PICKER MACHINE DELIVERING A LAP OF TEXTILE MATERIAL AND HAVING A FRAME AND A CONTROLLABLE DRIVE, AN APPARATUS FOR STOPPING THE PICKER ON DETECTION OF A FOREIGN ELECTRICALLY CONDUCTIVE BODY IN THE LAP, THE APPARATUS COMPRISING: A FIRST CALENDER ROLL HAVING AN ELECTRICALLY CONDUCTIVE ROLL SURFACE ELECTRICALLY INSULATED FROM THE FRAME, A SECOND CALENDAR ROLL IN ELECTRICALLY CONDUCTIVE RELATION TO THE FRAME AND NORMALLY OUT OF CONTACT WITH THE ROLL SURFACE OF THE FIRST ROLL, HIGH INPUT IMPEDANCE ELECTRICAL CIRCUIT MEANS ELECTRICALLY CONNECTED TO THE ROLL SURFACE OF THE FIRST ROLL FOR MAINTAINING THE ROLL SURFACE OF THE FIRST ROLL AT A LOW ELECTRICAL POTENTIAL RELATIVE TO THE FRAME, AND MEANS OPERATIVELY ASSOCIATED WITH THE CIRCUIT MEANS AND MACHINE DRIVE FOR DISENGAGING THE MACHINE DRIVE IN RESPONSE TO A FOREIGN ELECTRICALLY CONDUCTIVE BODY ELECTRICALLY CONNECTING THE ROLL SURFACE OF THE FIRST ROLL AND THE SECOND ROLL. 